Taking the fourth member of Quantou Formation ( K1q4 ) in the southern part of central Fuyu oilfield as an example,we systematically identified single sand bodies in the compound distributary channels of delta plain based on study of sedimentary microfacies with integrating various data including cores, well logging and production performance. The results show that K1q4 has well-developed large interconnected and banded compound distributary channel sand bodies of various origins in the study area. Detail characterization of single sand bodies reveals that there are 6 main superposition patterns, including multi-layers, overlapping, multi-boundaries, single-boundary, juxtaposition and isolation. Moreover,8 types of logging-facies marks of single sand bodies are identified for vertical timing and lateral boundary identification. The dense well pattern and small well spacing data in the study area are used to establish a quantitative prediction model for the width-thickness ratio of single sandbodies. By using this model, totally 44 single sand bodies of low sinuous meandering type are recognized in the5th to 10th layers of K1q4. These single sand bodies show a SW-NE trending banded distribution with a width of150 -500 meters,a thickness of 2 -8 meters,and a width-thickness ratio of 40 - 100. Tracer test results provethe accuracy of single sand body identification.%以扶余油田中区南部泉头组四段为例,在沉积微相研究的基础上,综合应用岩心、测井、动态等资料,对三角洲平原复合分流河道内部的单砂体进行系统识别.研究结果表明,研究区泉头组四段发育大面积连片状、条带状的多成因复合分流河道砂体.在单砂体精细解剖的基础上,发现该区单砂体主要包括多层式、叠加式、多边式、单边式、对接式、孤立式六种叠置关系,识别出单砂体垂向分期、横向分界的8种测井相标志.采用研究区密井网小井距资料建立了单砂体宽厚比定量预测模式,以此为指导,在研究区泉头组四段5-10小层内共识别出44个低弯度曲流型单砂体.这些单砂体在平面上主要呈西南-东北方向条带状展布,宽度介于150 ～ 500 m,厚度介于2～8m,宽/厚比介于40 ～ 100.最后,通过多组示踪剂分析测试资料,验证了单砂体划分的合理性.
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